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bb4eefe7bf
DocBook XML is superficially compatible with DocBook SGML but has a slightly stricter DTD that we have been violating in a few cases. Although XSLT doesn't care whether the document is valid, the style sheets don't necessarily process invalid documents correctly, so we need to work toward fixing this. This first commit moves the indexterms in refentry elements to an allowed position. It has no impact on the output.
115 lines
2.5 KiB
Plaintext
115 lines
2.5 KiB
Plaintext
<!-- doc/src/sgml/ref/drop_cast.sgml -->
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<refentry id="SQL-DROPCAST">
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<indexterm zone="sql-dropcast">
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<primary>DROP CAST</primary>
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</indexterm>
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<refmeta>
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<refentrytitle>DROP CAST</refentrytitle>
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<manvolnum>7</manvolnum>
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<refmiscinfo>SQL - Language Statements</refmiscinfo>
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</refmeta>
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<refnamediv>
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<refname>DROP CAST</refname>
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<refpurpose>remove a cast</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<synopsis>
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DROP CAST [ IF EXISTS ] (<replaceable>source_type</replaceable> AS <replaceable>target_type</replaceable>) [ CASCADE | RESTRICT ]
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</synopsis>
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</refsynopsisdiv>
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<refsect1 id="sql-dropcast-description">
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<title>Description</title>
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<para>
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<command>DROP CAST</command> removes a previously defined cast.
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</para>
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<para>
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To be able to drop a cast, you must own the source or the target
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data type. These are the same privileges that are required to
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create a cast.
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</para>
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</refsect1>
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<refsect1>
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<title>Parameters</title>
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<variablelist>
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<varlistentry>
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<term><literal>IF EXISTS</literal></term>
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<listitem>
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<para>
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Do not throw an error if the cast does not exist. A notice is issued
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in this case.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><replaceable>source_type</replaceable></term>
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<listitem>
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<para>
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The name of the source data type of the cast.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><replaceable>target_type</replaceable></term>
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<listitem>
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<para>
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The name of the target data type of the cast.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><literal>CASCADE</literal></term>
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<term><literal>RESTRICT</literal></term>
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<listitem>
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<para>
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These key words do not have any effect, since there are no
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dependencies on casts.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsect1>
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<refsect1 id="sql-dropcast-examples">
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<title>Examples</title>
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<para>
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To drop the cast from type <type>text</type> to type <type>int</type>:
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<programlisting>
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DROP CAST (text AS int);
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</programlisting></para>
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</refsect1>
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<refsect1 id="sql-dropcast-compat">
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<title>Compatibility</title>
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<para>
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The <command>DROP CAST</command> command conforms to the SQL standard.
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</para>
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</refsect1>
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<refsect1>
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<title>See Also</title>
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<simplelist type="inline">
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<member><xref linkend="sql-createcast"></member>
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</simplelist>
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</refsect1>
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</refentry>
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